Adaptive optic lens and method of making

ABSTRACT

An lens for correcting human vision, for example an IOL, contact lens or corneal inlay or onlay, that carries and interior phase or layer comprising a pattern of individual transparent adaptive displacement structures. In the exemplary embodiments, the displacement structures are actuated by shape change polymer that adjusts a shape or other parameter in response to applied energy that in turn displaces a fluid media within the lens that actuates a flexible lens surface. The adaptive optic means of the invention can be used to create highly localized surface corrections in the lens to correct higher order aberrations-which types of surfaces cannot be fabricated into and IOL and then implanted. The system of displacement structures also can provide spherical corrections in the lens.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 10/795,166,filed Mar. 6, 2004, which claims the benefit of U.S. ProvisionalApplication No. 60/453,010, filed Mar. 6, 2003. All of the aboveapplications are incorporated herein by this reference

FIELD OF THE INVENTION

The present invention pertains to an adaptive optic ophthalmic lens thatallows for post-fabrication modification that allows for correction ofhigher order aberrations or spherical errors. More in particular, theinvention can be used in IOLs, corneal inlay and onlays, contact lensesand the like wherein lens components respond to an external energysource, such as a laser, to allow adaptive structures at an interior ofthe lens to be altered in dimension to thereby adjust or flex the lensshape in a manner akin to methods used in the field of adaptive optics(AO) in astronomical telescopes.

BACKGROUND OF THE INVENTION

Post-fabrication adjustment of optical characteristics of lenses isneeded in various ophthalmic lens types. In one case, cataract patientswould benefit from post-implant power adjustability of an IOL implant.In another case, posterior chamber phakic IOLs could benefit frompost-implant power adjustability since biometry cannot insure properpower selection. Corneal inlays or similar types of lens also wouldbenefit from implantation of thin plano lenses followed by a laterexpansion of the lens to provide the desired refractive effect. Also,contact lenses would benefit from post-fabrication curvature adjustmentto limit the number of lenses that needed to be maintained ininventories.

Cataracts are major cause of blindness in the world and the mostprevalent ocular disease. Visual disability from cataracts accounts formore than 8 million physician office visits per year. When thedisability from cataracts affects or alters an individual's activitiesof daily living, surgical lens removal with intraocular lensimplantation is the preferred method of treating the functionallimitations.

In the United States, about 2.5 million cataract surgical procedures areperformed annually, making it the most common surgery for Americans overthe age of 65. About 97 percent of cataract surgery patients receiveintraocular lens implants, with the annual costs for cataract surgeryand associated care in the United States being upwards of $4 billion.

A cataract is any opacity of a patient's lens, whether it is a localizedopacity or a diffuse general loss of transparency. To be clinicallysignificant, however, the cataract must cause a significant reduction invisual acuity or a functional impairment. A cataract occurs as a resultof aging or secondary to hereditary factors, trauma, inflammation,metabolic or nutritional disorders, or radiation. Age-related cataractconditions are the most common.

In treating a cataract, the surgeon removes material from the lenscapsule and replaces it with an intraocular lens (IOL) implant. Thetypical IOL provides a selected focal length that allows the patient tohave fairly good distance vision. Since the lens can no longeraccommodate, the patient typically needs prescription eyeglasses forreading.

The surgeon selects the power of the IOL based on analysis of biometryof the patient's eye prior to the surgery. In a significant number orcases, after the patient's eye has healed from the cataract surgery,there is a refractive error was beyond the margin of error in thebiometric systems. Thus, there remain intractable problems incalculating the proper power of an IOL for any particular patient. Tosolve any unpredicted refractive errors following IOL implantation, theophthalmologist can perform a repeat surgery to replace the IOL—or thepatient can live with the refractive error and may require prescriptioneyeglasses to correct for both near and distant vision.

The correction of ocular wavefront aberration in ophthalmology is afield of increasing interest. Current diagnostic systems based on theShack-Hartmann (S-H) wavefront sensors can operate in real time,measuring the aberrations about every 40 msec. Besides the diagnosticspeed provided, there are other advantages of these new devices inocular wavefront aberration measurement, such as the use of infraredlight, and the fact that the systems use objective methods to simplifythe task of the subject.

At present, the only way to correct ocular aberrations beyondsecond-order is by customized refractive surgery such as in situkeratomileusis (LASIK). However, the corneal ablation approach willsuffer from many problems such as the complexity of controlling cornealbiomechanics and healing after surgery, and aberrations probably inducedby cutting the corneal flap that enables the ablation procedure.

Preliminary research has been done in correcting aberrations withaspheric customized contact lenses. This approach also faces practicallyinsurmountable problems relating to coupling lenses with eyeaberrations: (i) lens flexure will be a problem; (ii) tear film effectswill introduce spurious aberrations, and (iii) lens rotations and lenstranslation will limit the performance of the aberration correction.

In studies on large populations, it has been found that for a 5-mmpupil, the contribution to the total root mean square (RMS) wavefronterror of the second order is approximately 70% in highly aberrated eyesand 90% in young healthy eyes. If a lens were provided that couldcorrect include third order and spherical aberrations, the percentage ofthe population that could benefit from wavefront correction wouldincrease to 90% for highly aberrated eyes and to 99% for normal eyes.

Zernike polynomials are a set of functions that are orthogonal over theunit circle. They are useful for describing the shape of an aberratedwavefront in the pupil of an optical system. Several differentnormalization and numbering schemes for these polynomials are in commonuse. Fitting a wavefront to Zernike polynomials allows lens designers toanalyze the subcomponent aberrations contained in the total wavefront.Some of the lower order aberrations (also defined as Zernike polynomialcoefficients having an order (e.g., to first through fifth orderaberrations)) in a Zernike series are prism, sphere, astigmatism, coma,and spherical aberration.

A Zernike equation can include as many or few aberrations as requiredfor an application, for example, with more than 63 aberrations beyondsphere. Further explanations of higher order aberration can be found inthe following references: Macrae et al., Customized Corneal Ablation-TheQuest for SuperVision, Slack Inc., Thorofare, N.J. (2001); Thibos etal., Standards for Reporting the Optical Aberrations of Eyes, Trends inOptics and Photonics Vol. 35, Vision Science and Its Applications,Vasudevan Lakshminarayanan, ed., Optical Society of America, Washington,DC (2000), pp. 232-244; Atchison et al., Mathematical Treatment ofOcular Aberrations: a User's Guide, (2000). For the purposes of thisdisclosure, the adaptive optic corresponding to the invention isdesigned for the optional correction of higher order aberrations rangingat least above third order aberrations.

In view of the foregoing, what is needed is a lens system that providesmeans for post-fabrication or post-implant adjustment of opticalcharacteristics and dioptic power. What also is needed is a lens systemthat can correct higher order aberrations.

SUMMARY OF THE INVENTION

Of particular interest, the lens corresponding to the invention fallsinto the class of adaptive optics (AO) in the sense that micro-scaleactuator means are provided to flex and alter the curvature of the lenssurface locally for higher order aberrations or globally for sphericalcorrections, within a selected range of dimensions. The usual scope ofthe AO field encompasses flex-surface mirrors wherein piezoelectric orother drivers can flex the optical surface within microsecond intervalsto reduce aberrations, for example in astronomical telescopes as shownin FIG. 1A.

The actuators of the present invention differ completely in that theyonly need be actuated one time, or perhaps a few times, and there is noneed for rapid actuation response times. Still, the invention providesan AO structure wherein the adaptive optics comprise index-matcheddisplacement structures at a micro-scale suitable for correcting higherorder aberrations disposed in an interior of the lens. The actuators arein a fixed pattern in an interior lens phase with each having an indexthat matches the material of lens body, as indicated schematically inFIG. 1B.

In one preferred embodiment, the adaptive structure is responsive tolocalized energy application thereto, preferably in the form of lightenergy. In another embodiment, the actuator has an extending portionthat extends to the lens periphery to allow higher energy densities tobe used by providing a non-transmissive backing element.

A light source operating in the 400 nm to 1.4 micron range is suitable(not limiting) which will typically comprise a laser but other non-laserlight sources fall within the scope of the invention. The light sourceis coupled to a computer controller, galvanometric scanner (or any othertype of scanner), and optional eye-tracking system, all of which areknown in the art (e.g., in LASIK systems) and for this reason need nofurther description for adjusting an IOL. The micro-actuator means, ormore particularly the adaptive displacement structures are indicated inFIG. 1B, comprise a plurality of elements that define selected micronscale dimensions across principal and secondary axes thereof, whereinthe structures engage at least one deformable lens surface layer. In acontact lens, the light source can be less complex and need not bescanned as will be described below.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features of the invention, its nature and various advantageswill be more apparent from the accompanying drawings and the followingdetailed description of the preferred embodiments, in which:

FIG. 1A is conceptual view of AO (adaptive optics) as known in the artof deformable mirrors for astronomical telescopes with actuators at anexterior of the reflective mirror plane;

FIG. 1B is a conceptual representation of a lens element, for exampleand IOL or contact lens, including transparent index-matched softpolymer displacement structures or actuators at an interior plane of thelens in one embodiment of the AO (adaptive optics) structurecorresponding to the invention;

FIG. 2A is a perspective view of a Type “A” adaptive intraocular lens(IOL) with an interior phase carrying AO (adaptive optics) displacementstructures;

FIG. 2B is an exploded view of the components of the Type “A” adaptiveoptic of FIG. 2A showing the interior phase carrying the AO displacementstructures corresponding to the invention;

FIGS. 3A-3B are schematic illustrations of a first type of polymermonolith that functions as a displacement structure and its method offabrication in an isovolumetric refractive device;

FIGS. 3C-3D are schematic illustrations of a second type of polymermonolith that functions as a displacement structure and its method offabrication;

FIGS. 3E-3F are schematic illustrations of a third type of polymermonolith that functions as a displacement structure and its method offabrication;

FIGS. 3G-3H are schematic illustrations of a fourth type of polymermonolith that functions as a displacement structure and its method offabrication;

FIGS. 3I-3J are schematic illustrations of a fifth type of polymermonolith that functions as a displacement structure and its method offabrication;

FIG. 4 is an exploded view of an alternative Type “A” adaptive opticshowing the interior phase carrying the alternative displacementstructures corresponding to the invention;

FIG. 5A is a perspective view of another alternative Type “A” adaptiveoptic showing the interior phase carrying the alternative displacementstructures;

FIG. 5B is an exploded view of adaptive optic of FIG. 5A showing itsinterior phase and a non-transmissive peripheral element;

FIG. 6A is an enlarged cut-away view of a portion of the adaptive opticof FIGS. 2 and 3 showing its interior phase and features therein;

FIG. 6B is an enlarged cut-away view of the adaptive optic of FIG. 4showing its interior phase and features therein;

FIG. 6C is an enlarged cut-away view of the adaptive optic of FIGS.5A-5B showing its interior phase and features therein;

FIG. 7 is a perspective schematic view of an initial step in making aninterior phase of a Type “A” adaptive optic as in FIG. 6A correspondingto a method of making the adaptive optic utilizing drop-on microjetfluid dispensing;

FIG. 8A is an enlarged perspective view of the initial step of makingthe interior phase and Type “A” displacement structures of FIG. 6A of ashape memory polymer (SMP);

FIG. 8B illustrates following steps of the method of making the interiorphase and displacement structures of FIG. 6A including altering the SMPto its compacted temporary shape and adding an interior fluid layer tothe interior phase;

FIG. 9A illustrates the interior phase and displacement structure as isFIG. 8B assembled with a flexible anterior lens surface;

FIG. 9B illustrates the displacement structure as is FIG. 9A with thelens shape being modified in a wavefront aberration correctionprocedure;

FIG. 10 illustrates an alternative Type “A” adaptive optic wherein thedisplacement structures are coupled to the flexible lens surface;

FIG. 11A is an enlarged perspective view of the initial step of makingthe interior phase and displacement structure of FIG. 6B with a drop-onsystem;

FIG. 11B illustrates the next step of the method of making the interiorphase of FIG. 11A wherein a thin film heat shrink polymer is disposedover the displacement structure;

FIG. 11C illustrates the method of utilizing the interior phase anddisplacement structure of FIG. 6B wherein applied light energy shrinksthe heat shrink polymer to actuate the displacement structure;

FIG. 12A is an enlarged perspective view of the initial step of makingthe interior phase and displacement structure of FIG. 6C with a drop-onsystem;

FIG. 12B illustrates the next step of the method of making the interiorphase of FIG. 12A wherein a thin film cap layer is disposed over thedisplacement structure and two shape change polymer components;

FIG. 12C illustrates the method of utilizing the interior phase anddisplacement structure of FIG. 6C wherein applied light energy altersmultiple shape change polymers to reversibly actuate the displacementstructure;

FIG. 13A is a perspective view of the initial step of making analternative adaptive interior phase and displacement structures with adrop-on system into microfabricated wells in a substrate;

FIG. 13B illustrates the next step of the method of making the interiorphase of FIG. 13A wherein a thin film fluid permeable heat shrink caplayer is disposed over the displacement structures;

FIG. 14 illustrates a Type “B” adaptive optic with an alternativeinterior phase that is coupled to the flexible lens surface;

FIG. 15A illustrates an alternative Type “B” adaptive optic with analternative interior phase;

FIG. 15B illustrates the alternative interior phase of FIG. 15A afterbeing actuated;

FIG. 15C illustrates an alternative adaptive optic similar to FIG. 14but with overlapping interior phases for smoothing the lens surfacecurvature after independent actuation of structures in separate phases;

FIGS. 16A-16B illustrate any adaptive optic of the invention withlocations of a plurality of interior phases;

FIG. 17 is an adaptive optic of the invention with a photothermallysacrificial valve; and

FIGS. 18A-18B illustrate an adaptive optic with a plurality ofoverlapping interior phases that utilize the displacement structures ofFIGS. 3C-3F.

DETAILED DESCRIPTION OF THE INVENTION

I. Principles of Shape Memory in Polymers

Practically all embodiments of the invention utilize a shape memorypolymer (SMP) to enable fluid displacement, fluid handling and ingeneral actuation of the displacement structures of the adaptive opticaccording to the invention. For this reason, a background on shapememory polymers is provided. Some embodiments of the adaptive optic alsoutilize heat shrink polymers that are well known in the art, and it isnot necessary to provide additional background on such polymers.Collectively, the shape memory polymers and heat shrink polymers arereferred to herein as shape-change polymers.

Shape memory polymers demonstrate the phenomena of shape memory based onfabricating a segregated linear block co-polymer, typically of a hardsegment and a soft segment. The shape memory polymer generally ischaracterized as defining phases that result from glass transitiontemperatures in the hard and a soft segments. The hard segment of SMPtypically is crystalline with a defined melting point, and the softsegment is typically amorphous, with another defined transitiontemperature. In some embodiments, these characteristics may be reversedtogether with the segment's glass transition temperatures.

In one embodiment, when the SMP material is elevated in temperatureabove the melting point or glass transition temperature T_(g) of thehard segment, the material then can be formed into a memory shape. Theselected shape is memorized by cooling the SMP below the melting pointor glass transition temperature of the hard segment. When the shaped SMPis cooled below the melting point or glass transition temperature of thesoft segment while the shape is deformed, that temporary shape is fixed.The original shape is recovered by heating the material above themelting point or glass transition temperature of the soft segment butbelow the melting point or glass transition temperature of the hardsegment. (Other methods for setting temporary and memory shapes areknown which are described in the literature below). The recovery of theoriginal memory shape is thus induced by an increase in temperature, andis termed the thermal shape memory effect of the polymer. Thetemperature can be body temperature or another selected temperatureabove 37° C. for the present invention.

Besides utilizing the thermal shape memory effect of the polymer, thememorized physical properties of the SMP can be controlled by its changein temperature or stress, particularly in ranges of the melting point orglass transition temperature of the soft segment of the polymer, e.g.,the elastic modulus, hardness, flexibility, permeability and index ofrefraction. The scope of the invention of using SMPs in IOLs extends tothe control of such physical properties.

Examples of polymers that have been utilized in hard and soft segmentsof SMPs include polyurethanes, polynorborenes, styrene-butadieneco-polymers, cross-linked polyethylenes, cross-linked polycyclooctenes,polyethers, polyacrylates, polyamides, polysiloxanes, polyether amides,polyether esters, and urethane-butadiene co-polymers and othersidentified in the following patents and publications: U.S. Pat. No.5,145,935 to Hayashi; U.S. Pat. No. 5,506,300 to Ward et al.; U.S. Pat.No. 5,665,822 to Bitler et al.; and U.S. Pat. No. 6,388,043 to Langer etal. (all of which are incorporated herein by reference); Mather, StrainRecovery in POSS Hybrid Thermoplastics, Polymer 2000, 41(1), 528; Matheret al., Shape Memory and Nanostructure in Poly (Norbonyl-POSS)Copolymers, Polym. Int. 49, 453-57 (2000); Lui et al., ThermomechanicalCharacterization of a Tailored Series of Shape Memory Polymers, J. App.Med. Plastics, Fall 2002; Gorden, Applications of Shape MemoryPolyurethanes, Proceedings of the First International Conference onShape Memory and Superelastic Technologies, SMST InternationalCommittee, pp. 120-19 (1994); Kim, et al., Polyurethanes having shapememory effect, Polymer 37(26):5781-93 (1996); Li et al., Crystallinityand morphology of segmented polyurethanes with different soft-segmentlength, J. Applied Polymer 62:631-38 (1996); Takahashi et al., Structureand properties of shape-memory polyurethane block copolymers, J. AppliedPolymer Science 60:1061-69 (1996); Tobushi H., et al., Thermomechanicalproperties of shape memory polymers of polyurethane series and theirapplications, J. Physique IV (Colloque C1) 6:377-84 (1996).

The scope of the invention extends to the use of SMP foams for use inelastic composite structures, wherein the capsular shaping elementutilizes the polymer foam together with an expanse of nickel titaniumalloy. See Watt A. M., et al., Thermomechanical Properties of a ShapeMemory Polymer Foam, available from Jet Propulsion Laboratories, 4800Oak Grove Drive, Pasadena, Calif. 91109 (incorporated herein byreference). SMP foams function in a similar manner as the shape memorypolymers described above. The scope of the invention also extends to theuse of shape memory polymers that are sometimes called two-way shapememory polymers that can moved between two predetermined memory shapesin response to varied stimuli, as described in U.S. Pat. No. 6,388,043to Langer et al. (incorporated herein by reference).

Shape memory polymers foams within the scope of the invention typicallyare polyurethane-based thermoplastics that can be engineered with a widerange of glass transition temperatures. These SMP foams possess severalpotential advantages for intraocular implants, for example: very largeshape recovery strains are achievable, e.g., a substantially largereversible reduction of the Young's Modulus in the material's rubberystate; the material's ability to undergo reversible inelastic strains ofgreater than 10%, and preferably greater that 20% (and up to about200%-400%); shape recovery can be designed at a selected temperaturebetween about 30° C. and 45° C. which may be useful for the implants;and injection molding is possible thus allowing complex shapes.

As described above, these polymers also demonstrate unique properties interms of capacity to alter the material's water or fluid permeability,thermal expansivity, and index of refraction. However, the material'sreversible inelastic strain capabilities leads to its most importantproperty—the shape memory effect. If the polymer is strained into a newshape at a high temperature (above the glass transition temperatureT_(g)) and then cooled it becomes fixed into the new temporary shape.The initial memory shape can be recovered by reheating the foam aboveits T_(g).

II. Exemplary Ophthalmic Lenses Using Transparent Interior DisplacementStructures

1. Type “A” adaptive optic system.

The adaptive optic system of the invention can be used in any type oflens, such as an IOL (intraocular lens), a contact lens or a cornealinlay to allow for post-fabrication power adjustment or post-implantadjustment. For purposes of explanation, the principles of the inventionare first described with reference to an intraocular lens 10A forcataract treatment (FIG. 2A) adapted for in-the-capsule implantation.The three-piece IOL of FIG. 2A is shown with lenticular (lens) body 105having haptics arms 106 a and 106 b as are known in the art for lenscentration in an enucleated lens capsule.

In FIG. 2A, the IOL 100A has a lens body that defines a central opticportion 110 and peripheral non-optic portion 112 that is typically notdesigned for refraction, and may be transparent or non-transparent. Thelens body 105 defines an optical axis indicated at 115 and transverseaxis 116 that is perpendicular to the optical axis. The lens typicallyranges from about 5.0 mm to 6.5 mm in diameter (not limiting) for anin-the-capsule IOL with different diameters for inlays (e.g., 3.0 to 6.0mm.), anterior or posterior chamber lenses or contact lenses.

As can be seen in FIG. 2A and the exploded view of FIG. 2B, the IOLincludes an interior phase or layer 120 of the lens between the anteriorand posterior lenticular surfaces indicated at 122A and 122B. Theinterior phase 120 comprises a novel transparent adaptive layer that isdesigned to controllably flex at least an anterior thin flexible surfacelayer indicated at 124 a (FIG. 2B). In the embodiment of FIG. 2B, thecomplete lens is shown in exploded view with the interior phase 120assembled between the (first) anterior body layer 124 a and the (second)posterior body portion or layer 124 b, with both layers beingsubstantially fluid impermeable transparent polymers with any suitablerefractive index as is known in the art. It should be appreciated thatthe lens can any shape, such as bi-convex, plano-convex, plano-concave,convexo-concave or comprise a thin diffraction element.

More specifically, the lens interior phase 120 defines a plurality ofspaces 125 or volumes that carry a volume of a selected media M thatfunctions as a displacement structure for applying forces to displaceand deform the thin flexible surface layer 124 a to locally modify lenscurvature overlying the space 125. The terms spaces, displacementstructures and force-applying structures are used interchangeablyherein, identified by reference number 125, to describe the spaced apartadaptive structures that enable the adaptive optic and which aredesigned to actuate and deform and modify the shape of the surface layer124 a.

As can be seen in FIGS. 2A and 2B, the interior phase 120 definespattern of spaces or displacement structures 125 (collectively) in aspaced-apart fixed arrangement. Each displacement structure 125comprises a volume of selected media M that is alterable in a volumeparameter or other physical property to modify the local shape of thelenticular surface 122A. The structures 125 are at time referred to asforce-application structures herein since each such structure 125, orany collective number of actuatable structures, are capable of deformingthe lens surface 124 a by application of forces as each structure 125 isaltered from a first stable volume or shape to a second expanded volumeor shape. Of particular interest, the displacement structures 125 definea selected micro-scale that makes the system suitable for correctinghigher order aberrations. The displacement structures 125 also can beactuated globally to alter the spherical power of lens.

In the interior phase 120, each displacement structures 125 in theembodiment of FIGS. 2A and 2B is of a polymeric media that has an indexof refraction that matches body portions or layers 124 a and 124 b. Thelens according to the invention has in total from about 10 to 1000displacement structures 125. More preferably, the lens has from about 20to 200 such displacement structures 125 in a fixed pattern that aresuited to correct higher order wavefront aberrations.

The structures 125 also can be designed with similar or differentdimensions, volumes and amplitudes of adjustment for differentstrategies in post-implant correction of the lens. Typically, thedisplacement structures 125 are arranged in a pattern that definesconcentric circles 128 a-128 n about the optical axis 115. The number ofconcentric circles 128 a-128 n can range from 1 to about 500. Morepreferably, the concentric circles 128 a-128 n range from about 2 to 50.

The scope of the invention includes any adaptive optic for visioncorrection or other purposes that comprises a lens body formed with aplurality of microfabricated spaces 125 that carry media volumes of lessthan 1000 nanoliters therein. The lens body further defines flexiblesurface layer 124 a defining a surface region 140 overlying each spacethat is deformable toward or away from each said space when the mediatherein is actuated. By the term actuated, it is meant that the media isaltered in volume, porosity, hydrophilicity or pressure.

The displacement structures 125 are disposed in a fixed pattern, areindex-matched and are adapted to apply deforming forces to the flexiblesurface for lens power modification. The displacement structures 125 areprovided in a scale and number suitable for the correction ofpredominant aberrations, defocus and spherical aberration, as well ashigher order aberrations.

In one exemplary lens 10A, shown in FIGS. 2A and 2B, the displacementstructures 125 are of a transparent photo-modifiable polymer or a shapememory polymer in the classes described above. The shape memory polymeris of a type suited for the AO layer that actuates by expanding itsshape envelope to thereby apply displacement forces. In this embodiment,each displacement structure itself is targetable with a laser beam toadjust its dimension or envelope to thereby apply forces to a localportion of anterior surface 122A to modify its shape. More detailedillustrations of the displacement structures 125 of FIGS. 2A and 2B, themethod of making lens 100A and the method of use of lens 100A areprovided in FIGS. 3A-3B, 5, 7, 8A-8B and 9A-9B below.

FIGS. 3A-3L illustrate the principles of the adaptive displacementstructures corresponding to the invention, wherein each displacementstructure 145A-145F carries at least one shape change polymer that isphotomodifiable by thermal, chemical or other effects to cause fluiddisplacement in one of a number of manners. All such displacements offluids are designed to directly or indirectly apply deforming pressuresto a local portion or a flexible, adaptive lens surface layer. The useof a displaceable fluid layer 144 (see FIG. 2B, 3A-3B and 6A) to applypressure to a flexible lens surface is advantageous since it results insmooth radii of curvature of the actuated lens surface for bettercorrection of higher order aberrations that may require a plurality oflocal deformations.

In FIGS. 3A-3B, the single displacement structure 145A can be considereda cartoon of a refractive structure. A first polymer monolith 146A is ofa flexible polymer known in the art of IOLs and the second polymermonolith is a shape memory polymer 146B in its first temporary shape inFIG. 3A. FIG. 3A shows an incident light ray R and its refraction. Thecombined polymer monolith or structure 145A defines an interiorfluid-filled space 147 that actuates the adaptive optic by providing afluid 144 that interfaces with, supports and applies a displacementforce against a flexible lens surface 124 a that extends laterallybetween two lateral support regions to provide the lens surface withselected shape or curvature.

Of particular interest, the displacement structure 145A is anisovolumetric refractive structure wherein the net volume of the fluidand the first polymer monolith remains unchanged, but wherein actuationof the second shape memory polymer monolith 146B, in this case in avertical direction in FIG. 3A by photothermal effects from light beamLB, causes redistribution of fluid pressure in fluid media 144 indicatedby the arrows so that the fluid supports the laterally extendingportions of surface layer 124 a thereof. The first polymer monolith canoptionally have a flex-wall portion 148 outside the refractive portionof the displacement structure to accommodate some changes in fluidpressure. As can be seen if FIG. 3B, the light ray R is indicated withits modified refraction.

In FIGS. 3C-3D, another exemplary displacement structure 145B is similarto that of FIGS. 3A-3B except that the first polymer monolith 146A andthe second shape memory polymer monolith 146B are assembled to displacefluid 144 to the first space portion 147 as in FIG. 3B that actuates theadaptive optic and flexible lens surface 124 a with fluid 144 displacedfrom lateral space portion 147′. In other words, the shape memorypolymer monolith 146B functions as a displacement means or pump means todisplace fluid 144 to deform the flex surface over the interior spaceindicated at 147 (cf. FIG. 3B). The polymer 146B is altered byphotothermal effects as described above.

In FIGS. 3C-3D, the shape memory polymer 146B is shown as having asurface modification SM, which indicates that the polymer has a modifiedsurface that is substantially fluid impermeable to better displace thefluid. In some SMPs, the expansion of the polymer is a selecteddirection may require an in-fill media to fill open pores in the polymerif an open cell SMP is used, in which case the polymer would be providedwith a fluid media source internal or external to the implant (notshown) as can be easily understood to facilitate the expansion of thepolymer. This displacement structure 145B of FIGS. 3C-3D thus canincrementally and irreversibly displace fluid 144, and is used inseveral embodiments lens to actuate the adaptive optic, and is describedin more detail below.

FIGS. 3E-3F illustrate another exemplary displacement structure 145Cthat functions in opposite manner of the structure of FIGS. 3C-3D. Ascan be seen in FIG. 3E, the assembly again is of a first polymermonolith 146A (a non-shape change polymer) and the second shape memorypolymer monolith 146B that are assembled to displace fluid 144 from thefirst fluid-filled space portion 147 (as in FIG. 3B) that actuates thelens surface 124 a to the lateral space portion 147′ within thedisplacement structure 145C. In this embodiment, the shape memorypolymer 146B functions as a sponge-like displacement means to draw fluid144 into its interior spaces indicated at 147″ as it moves from itstemporary compacted shape (FIG. 3E) to its expanded memory shape (FIG.3F).

To accomplish this task, an open-cell permeable shape memory polymerfoam or CHEM is utilized which can expand to cause a potential interiorspace to expand to an actual interior space 147″ and suction fluid 144therein. In this embodiment, the fluid impermeable surface modificationSM is provided about an exterior of the displacement structure 145C.When used in an adaptive optic, the displacement structure 145C isdisposed about a periphery of the lens to provide a region for the SMPmonolith 146B to expand so as not to affect the refractive parameters ofthe lens. The displacement structure 145C of FIGS. 3E-3F canincrementally and irreversibly displace fluid 144, and can be combinedwith the structure 145B of FIGS. 3C-3D to provide a reversibledisplacement system with a predetermined amount of amplitude.

FIGS. 3G-3H illustrate another exemplary displacement structure 145Dthat functions as the structure 145B of FIGS. 3C-3D to displace fluid.In this embodiment, the structure again is of a first polymer monolith146A (a non-shape change polymer) and the second shape changeheat-shrink polymer monolith 146C that can displace fluid 144 to thefirst fluid-filled space portion 147 (as in FIG. 3B and 3D) to actuatethe lens. In this case, the to the lateral space portion 147′ within thedisplacement structure 145C. In this embodiment, the heat-shrink polymermonolith 146C displaces fluid 144 from the spaces portion indicated at147′ to the space 147 with the optic portion of the adaptive optic.

FIGS. 3I-3J illustrate another exemplary displacement structure 145Ethat functions as the structure 145C of FIGS. 3E-3F to displace fluid.This embodiment depicts that the polymer monolith 146D can be aco-polymer of a non-shape change polymer and second memory polymer, or aSMP monolith with a permeable non-collapsible layer 149 about thefluid-filled space portion 147′ which communicates with space portion147 (as in FIG. 3B and 3D) that actuate the adaptive optic.

In this case, the space portion 147′ is simply defined as a lumen in amonolithic wall that is at least partly an open-cell permeable shapememory polymer foam or CHEM. As described above, the displacementstructure can expand to cause a potential interior space to expand to anactual space indicated 147″ and can suction fluid 144 therein from theadaptive optic space 147. It should be appreciated that a heat shrinkpolymer can also simply be a tubular structure adapted for photothermalshrinkage to pump fluid 144 to a space 147 in the optic portion of theadaptive optic.

Now turning to another exemplary adaptive optic lens 100B that utilizesone of the fluid displacement structures just described in FIGS. 3A-3J,FIG. 4 illustrates a lens with an interior phase 120 that has aplurality of displacement structures 125 that first each and seconddisplacement structure portions 126 a and 126 b. The interior phase 120again is a thin layer that is enveloped by the anterior lens surface 124a and the posterior lens body 124 b, wherein an exploded view would besimilar to FIG. 3. The displacement structures 125 comprise aphotomodifiable thin film polymer 127 that envelops a flowable mediathat comprises the second structure portion 126 b.

In this embodiment, the flowable polymer 126 b can have a thermallystable property (as in a silicone) and the thin film 127 (first portion126 a) is of a polymer type that actuates by shrinking its shapeenvelope to thereby apply displacement forces-not to the lens surface124 a directly but to the enveloped flowable media therein. Thus, theshrinkage of thin-cross section portions 126 a will displace theflowable media to actuate swell the axial height of the seconddisplacement structure portion 126 a. An enlarged view of the actuationof an exemplary schematic is provided below in FIG. 3H, and thisintroduction is for the purpose of explaining that the shape changepolymers of the invention encompass SMP types that are expandable inenvelope to comprise an actuator and those that are heat-shrink types ofpolymers that are shrinkable in envelope to comprise an actuator.

In another exemplary lens 100C as shown in FIGS. 5A, the interior phase120 again has a plurality of displacement structures 125 with first andsecond photomodifiable polymers 128 a, 128 b that are coupled to theencapsulated flowable media 126 b as described in the previous lens 100Bof FIG. 4. The interior phase 120 again is a thin layer that isenveloped by the anterior lens surface 124 a and the posterior lens body124 b, with an exploded view in FIG. 5B.

Of particular interest, the first and second photomodifiable polymers128 a and 128 b are of both the types of polymers used in the lenses100A and 110B. The first photomodifiable polymer 128 a is an SMP typethat is expandable in envelope and the second photomodifiable polymers128 b is a heat-shrink type of polymers that is shrinkable in envelope.The combination of opposing shape effects in polymers is utilized toprovide displacement structures 125 that can actuate in two directionsfor a certain number of cycles.

In the exemplary embodiment of FIGS. 5A-5B, the first and secondphotomodifiable polymers 128 a and 128 b of each displacement structure125 are disposed in the periphery of the lens and are adapted to changevolume (or other parameter) to apply or reduce pressure on the flowablemedia 126 b which, in turn, applies forces to a local region of anteriorsurface 122A to modify its shape. The lens 100C of FIGS. 5A-5B allowsfor modification of lens shape exactly as lenses 100A and 100B of FIGS.2 and 4, except that the light energy can be targeted at the peripheryor non-optic portion 112 of the lens. This is advantageous for certainphoto-modifiable polymers that are adjusted with energy densities thatcould pose even a slight risk of damage to the retina. By positioningthe photo-modifiable polymers in the non-optic portion 112 of the lens,a non-transmissive composition or backing can be provided as indicatedat 130 in FIG. 4 to prevent any laser beam from irradiating thepatient's retina. More detailed illustrations of the lens 100C and itsdisplacement structures 125 as in FIGS. 5A-5B, its method of use andmethod of making are provided in FIGS. 11A-11D.

The scope of the invention includes the use of any displacementphotomodifiable media in or coupled to spaces 125 that can be actuatedto controllably alter a physical or chemical parameter thereof todisplace and deform a lens surface region over each space 125. Thephotomodifiable media can be a shape-change polymer, a polymer mediathat changes density or porosity in a fluid environment, anydisplaceable media such as a fluid or gel that is moved or pressurized,any combinations thereof.

In other words, each displacement structure 125 comprises media or acombination of media that is adjustable from a first stable functionalparameter to a second stable parameter in response to energy applied tolocations on the lens body to individually alter each displacementstructures 125, the functional parameters being in the class consistingof media volume, media shape, media porosity, media density and mediainternal pressure. As will be described below, the preferred method ofapplying energy to the lens body is the use of a laser or a non-coherentdirected light energy beam.

In FIG. 2, it can be seen that the anterior surface 122A of the lenscarries reference markers 132 about its periphery which may be providedin any suitable number, for example from 1 to 10. The reference marks132 are utilized to allow a light source and its computer-controlledscanning system to localize a light beam on a targeted location in thelens 100A. The reference marks 132 typically function based onreflectivity with a reference light beam and sensing system similar tothat used in a CD (compact disc), which is known in the art and need notbe described further herein.

2. Methods of making and using interior lens phase of Type “A” adaptiveoptic system.

The scope of the method of making the adaptive optic corresponding tothe invention, in general, covers the field of creating patternedadaptive features in an interior lens phase of an IOL or other visioncorrection lens or providing spaces 125 filled with a media by use ofprecision microjet dispensing of media droplets on a lens component in adata-driven manner. Various terms are applied to such accelerated fluiddroplet dispensing onto a targeted location on a substrate, and theterms microjet dispensing and drop-on dispensing will be usedalternatively herein. The drop-on system also is used to fill featuresmicrofabricated into lens components.

Such drop-on dispensing is novel and advantageous in adaptive opticfabrication since very small precise polymeric fluid volumes must becontrollably placed on or within a lens component. As a non-contactfluid dispensing process, the volumetric accuracy is not affected by howthe fluid polymeric media wets the substrate as may be the case whereinpositive displacement or pin transfer systems “touch off” a fluid onto asubstrate as it is dispensed. An additional advantage is that the jettedfluids can be dispensed onto or into substrate features such as wells orother features that are provided to control wetting and spreading of thefluid.

Drop-on dispensing can controlled single drop volumes as low as 5picoliters and as high as 5 nanoliters. Such precision fluid dispensingis capable of producing and placing “droplets” of polymeric fluids andfluids carrying nanoparticles, with micron-scale precision, with theindividual drops ranging about 10-200 μm in diameter, at dispensingrates of 0-25,000 per second for single droplets in a drop-on-demandsystem (described below) and up to 1 MHz for droplets in acontinuous-mode system (described below).

Of particular interest, the method allows for highly precise polymerdepositions in a data-driven manner to create the pattern ofdisplacement structures 125 in the interior phase 120 of any adaptiveoptic according to the invention. The method allows for polymerdeposition at a low cost (no tooling or molding required) in anoncontact, flexible and data-driven manner without masks, screens orthe like since the lens pattern and print information is createddirectly from CAD data stored digitally. Drop-on demand systems havebeen extensively investigated and developed (MatrixJet™ microdispensing)by MicroFab Technologies, Inc., 1104 Summit Ave., Ste. 110, Plano, Tex.75074.

In general, the physics and methods of microjet dispensing systems candiffer substantially, but each system variant provides a repeatablegeneration of small droplets of fluid media accelerated at a highvelocity from a jet onto a substrate. Two broad categories of fluiddispensing technologies for use in manufacturing are known: (i)drop-on-demand or demand mode systems, and (ii) continuous modecharge-and-deflect systems. These technologies are familiar to mostpeople in the form of desktop ink-jet printers.

In a drop-on-demand fluid dispensing system, the fluid is maintained atambient pressure and a transducer is utilized to create a droplet ondemand. The transducer creates a volumetric change in the fluid tocreate pressure waves that travels to a jet or orifice wherein thepressure is converted to fluid velocity-which results in a droplet beingejected from the jet. The transducer in drop-on-demand systems can bepiezoelectric material or a thin film resistor. In the later, theresistor causes a local fluid temperature to spike forming a vaporbubble which creates a volume displacement in the fluid media in asimilar manner as the electromechanical action of a piezoelectrictransducer.

In a “continuous mode” droplet dispensing system, a pressurized fluid isforced through an orifice, typically 25-80 μm in diameter, to form aliquid jet. Surface tension acts to amplify minute variations in the jetdiameter causing the jet to break up into drops—a behavior normallyreferred to as Rayleigh breakup. If a single frequency disturbance inthe correct frequency range is applied to the jetted fluid, thedisturbance will be amplified and drops of extremely repeatable size andvelocity can be generated at the applied disturbance frequency. Such adisturbance is generated by an electromechanical device (e.g., apiezoelectric element) that creates pressure oscillations in the fluid.This type of fluid dispensing is referred to as continuous-mode becausedroplets are continuously produced with their trajectories varied byelectrostatic charges. To control the extremely uniform dropletsgenerated by Rayleigh breakup, electrostatic forces are employed. Thecharged drops are directed to either the targeted location on asubstrate or to a catcher by a fixed electrostatic field called thedeflection field.

The drop-on-demand systems are much less complex than continuous-modesystems. On the other hand, demand mode droplet generation requires thetransducer to deliver three or more orders of magnitude greater energyto produce a droplet, compared to continuous mode, which relies on anatural instability to amplify an initial disturbance. Either system canbe used to accomplish the initial steps of fabricating the patternedinterior phase 120 of the invention.

Now turning to FIG. 6A, an enlarged cut-away view of a portion of thefirst exemplary Type “A” lens 100A of FIGS. 2-3 is shown. The spaces ordisplacement structures 125 carry a polymeric media that comprises anindex-matched photomodifiable shape memory polymer (SMP) as describedabove or in the literature identified above in Section I. The anteriorlens layer 124 a defines a selected thickness dimension A and modulus ofelasticity (E) so that a surface region 140 of layer 124 a (indicatedwith cross-hatching) cooperates with the surface area of space 125 toinsure that the radius of curvature in the deformed layer 124 a iswithin selected parameters. The thickness dimension A of the deformableanterior layer 124 a is from about 1 micron to 100 microns.

More preferably, the dimension A of anterior layer 124 a is from about 5microns to 50 microns. Still referring to FIG. 6A, the dimension B ofthe structure 125 across a principal transverse axis 116′ thereof (cf.transverse axis 116 of lens body 105 in FIG. 2) is less than about 2000μm (microns). More preferably, the transverse dimension A of thestructure 125 is from about 100 microns to 500 microns, and thedimensions can vary with in each concentric pattern of displacementstructures.

In FIG. 6A, it can be seen that the first and second polymer lensportions 124 a and 124 b envelope the interior phase 120 and an adjacentlayer of flowable media indicated at 144. The intermediate flowablemedia 144 again is a thin layer of index-matched fluid, a very lowmodulus index-matched material, or an indexed-matched gel or porousstructure with an index-matched fluid therein. In these exemplaryembodiments, this intermediate media 144 is adapted to occupy a lensvolume and provide stable refraction before and after adjustment lenswith actuation of the displacement structures 125.

In the embodiments that utilize a fluid 144, a silicone of a selectedviscosity can be used. Of particular interest for the invention,silicone fluids can be fabricated to provide the matching index ofrefraction as described above. Silicones change very little in viscosityover a wide temperature range, which together with their high wettingpower can will provide the properties needed for the functioning of theadaptive structure of lens corresponding to the invention. Further,silicones fluids are inherently inert towards the other substrates thatare anticipated to be used in the invention. All these characteristics,low viscosity change vs. temperature, dielectric stability, chemicalinertness, shear stability, low surface tension, oxidative stability,thermal stability and high compressibility make silicone a logicalcandidate for use in the invention.

Further, it is believed that silicone fluids, in this application, willbe found to be a biocompatible material for the interior of a lensimplant following FDA regulatory reviews. The viscosity of silicones orother suitable fluids is typically measured in units called centistokes(cSt) wherein the lower the number, the thinner and less viscous thematerial. A fluid 144 for use in the lens can have a viscosity rangingfrom about 0.65 cSt to about 1,000,000 cSt, which ranges from a very lowviscosity fluid upward to a high viscosity fluid. More preferably, thefluid 144 can have a fluid viscosity ranging from about 5.0 cSt to100,000 cSt, which at the upper range resembles a slow moving gel. Morepreferably, fluid 144 can have a fluid viscosity ranging from about 10cSt to 5,000 cSt.

A wide number of commercial sources of silicone fluids are known, forexample, NuSil Silicone Technology, Inc. (www.nusil.com); GeneralElectric, Inc. (www.gesilicones.com) and Dow Corning, Inc.(www.dowcorning.com). While silicone fluid is a preferred material foruse in the invention, it should be appreciated that hydrogels and anyother fluids fall with suitable matching indices, viscosities andbiocompatibility fall within the scope of the invention.

In the lens 100A of FIG. 6A, each structure 125 is actuated to deformthe surface portion 140 overlying the media by direct application andabsorption of energy by the shape memory media that defines structure125. The media can carry any suitable chromophore if required to absorbthe selected wavelength. Each structure 125 is assigned an address. Bythe term address, it is meant that the spatial location of thelenticular surface overlying the adaptive element is assigned surfacecoordinates in relation to reference markers indicated at 130.

In the exemplary lens 100A of FIG. 6A, the interior phase 120 comprisesa substrate 145 onto which the shape memory media is disposed, in amethod described in more detail below. It can be seen that theperipheral portion 112 of the lens has an increased cross-section space146 that carries a suitable volume of flowable media 144 that canmigrate about the region between the flexible surface 124 a and theactuatable interior phase 120 to fully occupy this space. The lensperipheral portion 112 overlying at least a portion of the increasedcross-section space 146 also has a flex-wall portion indicated at 148that can deform slightly to allow the migration of fluid 144 to or fromthe periphery after the displacement structures change in volume.

Now turning to FIG. 6B, a portion of the second exemplary Type “A” lens100B of FIG. 4 is shown in cut-away view. This lens 100B functions in asimilar manner as that of FIG. 6A to deform the lens surface 124 a, butas described above, utilizes a shape-change polymer that is of a heatshrink type. The displacement structure 125 thus comprises a firstportion that is a photomodifiable thin film polymer 127 that envelops aflowable media or the second structure portion 126 b. In thisembodiment, the thin film 127 first portion is photo-actuated toheat-shrink its shape envelope to expel fluid from the thereby applydisplacement forces to increase the axial height of the central portionof structure 125 to deform lens surface 124 a by inflow of the flowablemedia 126 b therein. In this embodiment, the heat-shrink shape envelopehas at least one (or a plurality) of extending portions indicated at 149(collectively). A plurality of extending portions 149 allow forindependent targeting with light energy to allow for a controlledshrinkage of an extending portions 149 to actuate the lens. A morecomplete description will be provided below when explaining the methodof making this interior phase 120.

Now turning to FIG. 6C, a portion of the third exemplary Type “A” lens100C of FIGS. 5A-5B is shown in cut-away view. This lens 100C displacesthe lens surface 124 a in a manner similar to that of FIGS. 6A and 6B,except that (i) the photo-actuatable polymer media is disposed in theperipheral portion 112 of the lens body, and (ii) both heat expandableand heat-shrinkable polymers (128 a and 128 b, respectively) areintegrated into the displacement structures 125 to allow reversibleactuation. As discussed above and shown in FIG. 5B, this embodimentallows the use of higher fluences to actuate the shape-change mediasince the peripheral non-optic lens body 112 can carry a nontransmissive composition 130 (see FIG. 5A) posterior of the targetedphotomodifiable media.

In the lens 100C of FIG. 6C, the spaces or displacement structures 125define a first space portion 125′ and second space portion 125″ that arecarried again interior phase 120. In this embodiment, the interior phase120 essentially floats within the flowable media layer 144. Pegstructures (not shown) between members 124 a and 124 b though aperturesin phase 120 can maintain the phase in a fixed location to preventlateral migration.

The first space portion 125′ of the displacement structure space is inthe optic portion 110 of the lens and is adapted to change in volume andaxial dimension to deform the overlying surface region 140 exactly asdescribed in the text above accompanying FIG. 6A. The first spaceportion 125′ carries the flowable media 126 b that interfaces with firstand second shape-change polymers 128 a and 128 b disposed in the secondspace portion 125″ within the lens periphery 112.

It can be easily understood how the expansion or contraction of thefirst and second shape-change polymers 128 a and 128 b in the secondspace portion 125″ can thereby cause fluid pressure and media flow toactuate the displacement structure. As can be seen in FIG. 6C, the shapechange polymer and the flowable media 126 b in first space portion 125′are sealably carried in the interior phase which has base substrate 145and overlying cap layer 176 that can be fabricated in various manners asdescribed below. All other aspects and dimensions of the lens componentsare similar in lens 100A, 100B and 100C of FIGS. 6A-6C.

Now turning to FIGS. 7 and 8A-8B, the steps of making and using theinterior lens phase 120 that is the core of the adaptive optic is shownschematically. In FIG. 7, the substrate 145 can comprise any very thinpolymer film that is disposed on the stage of the drop-on microjetsystem 160 wherein a plurality of interior phase components can befabricated contemporaneously, with each round substrate portion latercut from the film to make an interior phase 120.

In the fabrication of the interior phase 120 of the lens 100A of FIG.5A, the drop-on system disposes a shape memory polymer media in a firststate as described above to create the desired pattern in concentriccircles 118 a-118 n. The droplets 162 can be used to create thedisplacement structures 125 in a desired volume ranging between about100 picoliters and 1000 nanoliters.

FIG. 8A is a greatly enlarged view of two displacement structures 125after being disposed on the substrate and polymerized or partiallypolymerized to define a memory shape with given axial height. FIG. 8Bnext illustrates the two displacement structures 125 of FIG. 8A afterbeing compacted mechanically to second temporary state with an axialheight C wherein a polymer segment of the SMP is polymerized to maintainthe structure in its compacted state. The media can be shape memorypolymer foam as described above. FIG. 8B also illustrates the fluidlayer 144 disposed over the interior phase 120 by any suitable meanssuch as drop-on dispensing or a similar spray-on system.

Fluid layer 144 also can comprise a thin gel layer or a photoscissablepolymer that is provided in a gel or solid form and converted to a fluidby energy delivery after assembly of the lens components 120, 124 a, 124b and 144. The interior phase 120 and displacement structures 125 ofFIG. 8B are actuated by energy deliver by a beam from a light source,wherein the structure is returned toward its memory axial height.

FIGS. 9A and 9B show the actuation of the displacement structures 125when assembled with the deformable lens surface 124 a and base layer 124b to illustrate the shape change of region 140 overlying the structure125. In FIG. 9B, it can be seen how fluid or gel layer 144 will migrateto occupy the entire space between the interior phase 120 and thedeformable lens surface 124 a to provide a continuous lens interior ofindex matched media.

FIG. 10 shows an alternative lens 100C that shows the displacementstructures 125 being disposed directly onto a lens layer 124 a (it thenbeing flipped over) to assemble with base layer 124 b. The sealing oflens layers 124 a and 124 b can be accomplished in various manner suchas adhesives or providing cooperating polymer precursors in each layerand thereafter fully polymerizing the assembly. In another method, thedisplacement structures 125 can be dispensed onto an applanated baselayer 124 b that is then assembled with fluid layer 144 and lens surfacelayer 124 a.

Now turning to FIGS. 11A-11C, the steps of making and using interiorlens phase 120 of lens 100B of FIG. 6B are shown. In FIG. 11A, thedrop-on system 160 is used to dispense flowable media 126 b ontosubstrate 145 in a pattern indicates with at least one extending portion129. In this embodiment, one extending portion 129 is shown but thenumber can range from 1 to 6 or more.

In one method, a larger volume of media 126 b can be dispensed in thecentral portion with a first surface tension and then (optionally) beirradiated and partly polymerized to increase it surface tension, andthereafter another volume of flowable media 126 b can be drop-ondispensed to provide the extending portions 129 at a second surfacetension. Thus, the method of the invention included intermediate stepsto alter the surface tension of media portions or the use of differentindex-matched media with different surface tensions to createdisplacement structure with different portions having different axialheights.

FIG. 11B illustrates the next step of the method wherein a heat-shrinkor shape change polymer is sprayed on with system 162 or dispensed usingdrop-on technology to envelop the flowable media 126 b to thereby allowit to flow from the spaces 129 to the more central space portion 125 todisplace the overlying lens region 140 exactly as described above inFIG. 9B. In this embodiment, the flowable media 126 b can be induced toflow under a photomodifiable polymer capping layer 127 which seals theentire displacement structure 125 in the microfabricated interior phase120.

In one method depicted in FIG. 11B, the thin layer 127 is fabricated bydrop-on or spray dispensing of an index-matched heat shrink polymerprecursor over the assembly which is then polymerized into a thin filmcoating by any suitable means such as UV curing. In another method notshown in the Figures, a cap layer 127 is provided in the form of athin-film heat-shrink substrate that is sealably formed over theassembly as in FIG. 11B.

FIG. 11C next shows the method of utilizing a laser or light source toactuate the displacement structure 125 by applying light energy to theheat shrink layer 127 in a peripheral extending portion 129 whichimpinges on the volume therein to displace flowable media 126 b tocentral portion which moves axial height C′ from the lesser height C ofFIGS. 11B. The heat shrink polymer of FIGS. 11A-11C can thus be definedas a type of pump means to displace flowable media 126 b to actuate thedisplacement structure 125. The interior phase of FIG. 11C would operateto deform a lens surface layer 124 b exactly as in FIG. 9B with fluidlayer 144 (not shown) again in-filling the region around the actuateddisplacement structure 125. Thus, for convenience, the steps ofillustrating the displacement structure 125 of FIG. 11C together with anoverlying deformable lens layer 124 a are not provided.

Now turning to FIGS. 12A through 12C, the steps of making and using theinterior lens phase 120 of lens 100C of FIG. 6C are is shown. FIG. 12Ashows that the non-transmissive layer 130 can be fabricated on substrate145 by any suitable means such as printing, bonding a non-transmissiveannular element or the like. In FIG. 12A, the first and secondshape-change polymers 128 a and 128 b of the displacement structure 125can be created by drop-on dispensing or another preliminary operation toprovide an expandable shape-change polymer 128 a portion and a heatshrink polymer portion 128 b in a peripheral region 112 of the optic andsubstrate 145. The shape memory shrink polymer is a foam or CHEM asdescribed above with a potential interior open volume with the SMPstructure in a compacted temporary shape.

Upon photothermal modification, the SMP's expansion will draw flowablemedia 126 b into the open interior of the foam network to subtract fromthe volume of first space portion 125′ within the optic portion 110 ofthe lens to thereby decrease its axial dimension C. The heat shrinkpolymer structure 128 b, for example, is a reticulated, porous,channeled or it can also be a thin-film structure with a single interiorlumen-the polymer being in a non-shrunken state in its initial deployedstate. Further, the open interior of the heat shrink polymer structure128 b is infused with flowable media 126 b in a preliminary operation ofby the drop-on dispensing step described next.

FIG. 12A further illustrates the step of the method that is similar tothat of FIGS. 7 and 8A wherein a flowable media 126 b is drop-ondispensed in and along space 125″ to operatively interface with theperipheral substrate region carrying the first and second shape-changepolymers 128 a and 128 b configured thereon. As described in the textaccompanying FIGS. 11A-11C, the flowable media 126 b can be providedwith varying depths and surface tensions.

FIG. 12B next illustrates the fabrication of a cap layer 176 over theentire assembly of the first and second shape-change polymers 128 a, 128b and flowable media 126 b to seal the volume of exchangeable flowablemedia therein to provide a photoactuatable displacement structure 125.One method depicted in FIG. 12B is fabricating the thin film cap layer176 by use of a spray-on system 162 that disperses an index-matchedpolymer over the assembly which is then polymerized into a thin filmcoating. As described previously, such a cap layer 176 also can beprovided in the form of a thin-film polymer substrate sealably formedover the displacement structure assembly.

FIG. 12C next shows the method of utilizing a laser or light source toactuate the displacement structure 125 by applying light energy toregion 180 of the heat shrink polymer portion 128 b wherein photothermalabsorption cause shrinkage of region 180 to thereby expel flowable media126 b therefrom which in turn drives a flow (see arrows) into spaceportion 125′ to move the structure to a greater axial height C′ from thelesser height C of FIG. 12B. The shape change polymer 128 b of FIG. 12Cfunctions in effect to pump and displace flowable media 126 b to actuatethe displacement structure 125 in an axial dimension. This interiorphase of FIG. 12C operates to deform a lens surface layer 124 b exactlyas in FIG. 9B with fluid layer 144 again in-filling the region aroundthe actuated displacement structure 125. For convenience, FIG. 12C doesnot illustrate the lens surface layer 124 b and intermediate fluid layer144.

FIG. 12C also depicts in phantom view the method of utilizing appliedlight energy to reversible actuate the displacement structure 125 byapplying light energy to region to a region of shape memory polymerportion 128 a wherein the photothermal effect therein causes expansionof local region 182 to thereby draw flowable media 126 b into the openinterior of the polymer 128 a to thereby reduce the axial height of thespace 125.

Thus, the invention provides for reversible actuation of thedisplacement structure 125. It can be appreciated that the system can beutilized to reversibly actuate the displacement structure 125 to alterits axial amplitude a number of times determined by the dimensions andvolume of the shape change polymer portions 128 a and 128 b. By thismeans, the lens region 140 overlying each actuator can be reversiblyactuated and provided with a known maximum range of amplitude forcorrection of wavefront aberrations or together with a plurality ofother actuators to alter the spherical shape of the lens.

FIGS. 13A and 13B illustrate an alternative Type “A” embodiment ofadaptive optic 100E wherein the interior adaptive phase 120 comprises asubstrate 145 with displacement structures or spaces 125 that are formedin microfabricated wells 190 (collectively) with two such wells 190 aand 190 b depicted. The substrate also can be either the anterior orposterior lens body layers 124 a and 124 b as in FIG. 2.

FIG. 13A illustrates the wells 190 being filled with a drop-ondispensing system 160 with a shape memory polymer foam media 192 beingdispensed therein with the media having substantial surface tension toprovide a highly bulged memory shape relative to the surface of thesubstrate. FIG. 13B next illustrates several steps of making and usingthe interior phase 120. First, the shape memory polymer media 192structures are all compacted to a stressed temporary shape whichconforms with the surface of substrate 145.

FIG. 13B also illustrates the placement and bonding of a thin film 195to substrate 145 over the displacement structures 125. The bonding canbe completely across the substrate or along lines indicated at 196 thatare spaced apart from the shape memory polymer media 192. In a method ofuse, it can be understood that the media 192 in well 190 a can beexpanded by photothermal absorption from a first wavelength indicated atλ₁ to an increased axial height indicates at C′. It also can beunderstood that irradiation of heat shrink thin film 195 can causecontraction of the expanded SMP foam as indicated in well 190 b in FIG.13B wherein the structure's height may be altered from C′ to at C″.

Preferably, a second wavelength indicated at λ₂ is used for theirradiation of the heat shrink polymer. In an alternative embodiment,the glass transition temperature of the SMP and the shrink temperatureof the film can differ to allow different heat levels to actuate thedisplacement structures 125 in opposing directions.

The scope of the invention and the method of making an adaptive opticincludes the drop-on microjet dispensing of precise polymer volumes inmicrofabricated wells of any lens component, as in the any of thedisplacement structure types of FIGS. 2, 4, 5, 6A-6C and 10.

3. Type “B” adaptive optic system.

FIGS. 14 and 15A-15B illustrate an alternative adaptive optic 200A thatcan be understood by the cut-away view of only an edge portion of thelens body 205. In this embodiment, the interior phase 220 is of aresilient index matched porous heat shrink polymer form indicated at222. The form 222 has concentric formed undulations 225 a thereinwherein the anterior and posterior peaks of the undulations are bondedto the first and second lens body layers 124 a and 124 b.

The lateral space 226 that contains the interior phase 220 is filledagain with index matched fluid 144 as in the Type “A” embodiments above(with the peripheral expansion space for fluid 144 not shown). Thestructure of the undulation 225 a is sufficiently resilient to maintainthe space 226 in an open position as in FIG. 14 after unfoldingdeployment. It can be easily understood that the interior phase 220 canbe irradiated at predetermined locations or addresses 228 a, 228 b etc.at the surface layer to shrink the polymer to thereby inwardly displacethe surface layer to cause power adjustment (cf. FIG. 15B). In thisadaptive optic type, the lens would be implanted with an over steepcurvature and the interior phase is adapted to reduce curvature.

FIGS. 15A and 15B illustrate an alternative embodiment wherein theinterior phase 220 again is of a resilient index matched porous heatshrink material but with formed domes 225 b rather than undulations asin FIG. 14. The scope of the invention thus covers any resilientinterior phases 220 that define surface relief for maintaining spacingacross interior space 226. The anterior dome surfaces are bonded to theanterior layer 124 a so that contraction of the dome will actuate anddepress the region of the surface layer overlying the structure 225 bupon irradiation as depicted in FIG. 15B. In effect, the actuatorfunctions in the opposite manner of that of the Type “A” embodiment.

FIG. 15C illustrates an adaptive optic with three interior phases 222a-222 c that overlap to allow for smooth change in surface radii. Ofparticular interest, one phase can be adapted apply positive verticalforces, and a second phase can be adapted to subtract from verticalforces for a reversible system. Also, the fluid in the interior phasescan of a type that can be fully polymerized by any type of photo-curingafter distribution among the displacement structures to set a finalshape.

Without repeating the drawings of the Types “A” and “B” embodimentsabove, it can be easily understood that first and second interior phases220 and 220′ of the Types “A” and “B” displacement systems,respectively, can be combined to provide a reversible actuation system.FIGS. 16A and 16B illustrate such a lens 200B with the dual phases 220and 220′ in an anterior location and in spaced apart locations.

4. Type “C” adaptive optic system.

FIG. 17 illustrates an alternative adaptive optic 300 that can beunderstood again by the cut-away view of the peripheral portion of thelens body 305. In this embodiment, the interior phase 320 again carriesa plurality of fluid-filed displacement structures indicated at 325.Each such structure is somewhat pressurized after the lens is implanteddue to intraocular pressure.

The peripheral region of the lens has a sacrificial valve 328 or acontrollable release valve that can be photothermally actuated torelease fluid media 340 from each displacement structure 325 wherein thefluid will flow to an internal chamber collapsed flexible sac chamber342 in the lens periphery. In substance, this system functionsapproximately as the Type “A” embodiment wherein a collapsed porous SMPstructure is photothermally altered to allow fluid flow therein ortherethrough.

Without repeating the drawings of the Type “A” embodiments above, it canbe easily understood the displacement structure types of FIGS. 6A-6C inan interior phases 120 can be combined with the sacrificial valve 328 ora controllable release valve of FIG. 17 to provide a reversibleactuation system.

5. Type “D” adaptive optic and method of making.

FIGS. 18A and 18B illustrate an alternative adaptive optic 400A, showingonly cut-away views of the peripheral portion of an exemplary lens body405 of a resilient hydrogel, acrylic, silicone or other similarmaterial. This lens embodiment again carries a plurality of fluid-fileddisplacement structures or spaces indicated at 425 identifiable asaddresses 228 a, 228 etc. at the lens surface. This lens differs in itsmethod of fabrication. In this embodiment, the lens body is fabricatedby molding, casting or turning and polishing or in any other mannerknown in the art of IOL fabrication to provide a finished lens bodyhaving a known power and shape. In other words, this lens can be made bystarting essentially with an off-the-shelf lens. As will be describedbelow an additional peripheral shape change polymer component 440 isrequired.

FIG. 18A illustrates the method of fabricating the spaces 425 in thelens body to provide a thin resilient deformable layer 442 over eachspace 425. In FIG. 18A, a femtosecond laser as known in the art isfocused to deposit energy in an inner layer of the plane or phase 420 oflens body 405 in a very short time interval such as fs or ps. As theenergy is transferred from the laser beam, a plasma formation occurs andthe material is removed or ablated to create a space 425.

In the lens material, the distance over which the heat due to laserenergy is dispersed is less than the absorption length of the laser,thereby allowing volumetric removal of material before energy losses dueto thermal diffusion can occur and overheat the polymer. The science ofutilizing femtosecond is well established and need not be describedfurther. It can be seen in FIG. 18A that this approach canmicrofabricate spaces 425 and channels portions 425′ of the spaced thatextend to a peripheral non-optic portion 112 of the lens body. Afterfabrication of the lens, the interior spaces and channels are flushedand filled with a fluid 444 that is index-matched to the lens body tore-occupy the spaces 425 and the lens will then have its original shapeand power.

In order to alter the lens shape, any polymer shape adjustable system asillustrated in FIG. 6C is utilized to cause fluid flows into or out ofthe chambers by irradiation of the targeted polymer indicated at 440 inany sub-pattern of locations 440 a, 440 b, 440 c etc. in the lensperiphery that are fluidly coupled to each space 425. FIG. 18Billustrates an alternative lens 400B which is in all respects similar tothe lens of FIG. 18A except that the adaptive spaces 425 are carried ina plurality of interior phases or layers 420 and 420′ wherein the spacesare offset from one another wherein independent actuation of variousphases will allow for the creation of substantially smooth lens surfacecurvatures.

The scope of the invention extends to microfabrication of an adaptiveoptic with a plurality of interior phases or layers by conventionalmolding or casting and assembly techniques known in the art.

The scope of the invention extends to microfabrication of an adaptiveoptic by creating a porous polymer block monolith in the shape of a lenswherein the pore are filled with an index-matched fluid media andwherein the body portion are globally polymerized and by photo-curingwith a scanned focused light energy delivery to fully polymerized theentire lens block with the exception of spaces and channels that extendto any of the displacement structures of FIGS. 3A-3J and 18A-18B thatare assembled within or bonded to the optic's periphery.

The scope of the invention extends to any adaptive optic that has mediadisplacement means coupled to each interior space as in FIG. 2 thatcomprises a non-mechanical pump selected from the class ofelectroosmotic, electrohydrodynamic and magnetohydrodynamic pump systemsas are known in the art. The scope of the invention extends to anyadaptive optic that has media displacement means coupled to eachinterior space as in FIG. 2 that comprises a mechanical pump selectedfrom the class of thermohydraulic micropump systems,thermopnematic-assisted pump systems, and thermoperistaltic systems.

In any of the above-described embodiments, the intraocular lens can becombined with a wavefront sensing system (e.g. a Shack Hartman system)to allow computer-controlled correction of the aberrations in theadaptive optic of the invention.

The scope of the invention extends to any adaptive optic as describedabove for non-ophthalmic uses. For example, an adaptive optic can bedeveloped with a resilient lens body have at least one interior phasewith each of the plurality of displacement structures (actuators)comprising a space filled with an index matched fluid therein. Eachdisplacement structure is coupled to a fluid-filled peripheral space,fluid source (or remote chamber) outside the lens optic portion that iscoupled to a real-time computer controller to control the volume andpressure of each displacement structure in the interior lens phase tomodulate lens shape at a high repetition rate.

Such an adaptive optic can be readily fabricated with microfluidicchannels and pumps, controllers and a wavefront sensor for wavefrontcorrection in imaging and beam forming systems for opticalcommunications, biomedical imaging, astronomical instruments, militarylaser focusing, aviation and aerodynamic control, laser beam and cavitycontrol and laser welding and other similar uses. The lens generally isrepresented in FIG. 2. It is postulated that such an adaptive optic canbe microfabricated economically and be far more robust for certainoperating environments than micro-mirror arrays and lenses that arebeing developed and known in the art.

Those skilled in the art will appreciate that the exemplary embodimentsand descriptions thereof are merely illustrative of the invention as awhole, and many variations may be made within the spirit and scope ofthe invention. Specific features of the invention may be shown in somefigures and not in others, and this is for convenience only and anyfeature may be combined with another in accordance with the invention.

1. An isovolumetric refractive structure for an ophthalmic device,comprising a first polymer monolith with an interior fluid-filled space,a second polymer monolith interfacing said interior fluid-filled space,said second polymer monolith of a shape modifiable polymer thatmodifiable between first and second shapes, and wherein actuation of thepolymer to said second shape from said first shape irreversibly causesfluid displacement about said interior space to alter the refractiveparameters of the structure without a change in net volume.
 2. Anisovolumetric refractive structure of claim 1 wherein the shapemodifiable polymer is fluid impermeable.
 3. An isovolumetric refractivestructure as in claim 1 wherein the shape modifiable polymer has a fluidimpermeable surface layer.
 4. An isovolumetric refractive structure asin claim 1 wherein the shape modifiable polymer is fluid permeable. 5.An isovolumetric refractive structure as in claim 1 wherein the shapemodifiable polymer is an open cell foam.
 6. An isovolumetric refractivestructure as in claim 1 wherein the shape modifiable polymer is bondedto the first polymer monolith.
 7. An isovolumetric refractive structureas in claim 1 wherein the first and second polymer monoliths and thefluid of said fluid-filled space have matching indices of refraction. 8.An isovolumetric refractive structure as in claim 1 wherein the shapemodifiable polymer defines an absorption coefficient that cooperateswith a selected wavelength ranging between the UV and the IR to permitthermal effects therein.
 9. A fluid displacement structure for anophthalmic implant, comprising a polymer block at least partly of ashape memory polymer that defines a temporary shape and a memory shape,the block defining an interior space wherein actuation of the shapememory polymer to said memory shape from said temporary shapeirreversibly causes fluid displacement within said interior space.
 10. Afluid displacement structure as in claim 9 wherein said interior spaceis within open cells of the shape memory polymer.
 11. A fluiddisplacement structure as in claim 9 wherein said interior space isselected from that class consisting of microchambers and microchannelshaving an dimension across a principal axis of less than 1000 microns.12. A fluid displacement structure as in claim 9 wherein the shapememory polymer is fluid impermeable.
 13. A fluid displacement structureas in claim 9 wherein the shape memory polymer has a fluid impermeablesurface layer.
 14. A fluid displacement structure as in claim 9 whereinthe shape memory polymer is fluid permeable.
 15. A fluid displacementstructure for an ophthalmic implant, comprising a polymer block at leastpartly of a heat shrink polymer, the block defining an interior spacetherein for carrying a fluid and wherein thermal shrinkage of the heatshrink polymer irreversibly causes fluid displacement within saidinterior space.
 16. A fluid displacement structure of claim 15 whereinsaid interior space is selected from that class consisting ofmicrochambers and microchannels having an dimension across a principalaxis of less than 1000 microns.
 17. An adaptive optic for visioncorrection comprising a lens body defining an optical axis and atransverse axis, the lens body formed with a plurality ofmicrofabricated spaces therein, each space having a dimension across itstransverse axis of less than about 1000 μm, wherein the lens bodydefines flexible surface regions overlying each space that deform overeach said space when a media therein is actuated.
 18. An adaptive opticas in claim 17 wherein the microfabricated spaces define an interiorphase of the lens body that is operatively coupled to a flexible surfacelayer of the lens body.
 19. An adaptive optic as in claim 17 wherein theinterior phase carries the spaces in a fixed pattern about the opticalaxis of the lens body.
 20. An adaptive optic as in claim 17 wherein themedia in the spaces defines an index of refraction that matches theindex of refraction of the lens body.
 21. An adaptive optic as in claim17 wherein the spaces range in number from about 2 to
 200. 22. Anadaptive optic lens as in claim 17 wherein the space defines a firstportion within a central optic region of the lens body and a secondportion within a peripheral region of the lens body.
 23. An adaptiveoptic lens as in claim 22 wherein said second portion of each spaceprovides at least one media displacement means.
 24. An adaptive opticlens as in claim 23 wherein said media displacement means comprises apolymer portion that actuates to displace said media volume.
 25. Amethod of making an adaptive ophthalmic lens, comprising the steps of:(a) providing a first polymer substrate; (b) dispensing a selected fluidmedia onto said first substrate to provide an interior phase comprisinga plurality of displacement structures disposed in a fixed pattern overa lateral region of said interior phase; and (c) sealing a secondpolymer substrate over the first polymer substrate to envelope theinterior phase therebetween.
 26. A method as in claim 25 wherein step(b) includes the step of providing a shape memory polymer operativelycoupled with said plurality of displacement structures to alterdisplacement pressure therein, the shape memory polymer defining atemporary state and a memory state.
 27. A method as in claim 25 whereinsteps (a) and (b) provide the first and second polymer surfaces and theinterior phase in matching indices of refraction.